Surface wettability of the microporous ceramic tube and measurement of its porosity

Pore structure of porous ceramic tube prepared by the hot forming method is studied by mercury method to obtain pore distribution of ceramic membrane. Self-developed three-phase interface analyzer is used to measure the wetting phenomena of tin which is one of the low melting point metals on the alumina ceramic tube membrane at the temperature from 240 ℃ to 640 ℃. It is found that the contact angle of tin on ceramic tube membrane at the range of temperature is greater than 150 °, and the wettability of the both is poor. Based on image processing technology and theoretical calculations, a method to measure penetration rate of droplets on porous surface is proposed and a velocity equation of the droplets which penetrate to the porous ceramic tube is deduced. The oil droplet is tested to find out that the droplet spreads firstly during infiltration process and it maintains its spreading radius for a period of time until it fully penetrates into ceramic tube membrane.